In the discussion of “What is the optical refractive index of an eye lens?” When it comes to this problem, we first need to understand the physical concept of optical refractive index, ...
The fashion industry is setting off a wave of retro round glasses, becoming a high-profile fashion item at the moment.
Round retro glasses with its classic shape and unique charm, quickly captured ...
Optometric data
Accurate degree: Go to a professional eye institution or optician for optometry to obtain accurate myopia, farsightedness, astigmatism degree and axial position data. This is the ba...
What is cellulose acetate?
Cellulose acetate refers to a thermoplastic resin obtained by esterification with acetic acid as a solvent and acetic anhydride as an acetylating agent under the action o...
Choose the right sunglasses
Uv protection: To ensure that sunglasses can effectively block ultraviolet light, the label is usually marked with UV400 and other signs, indicating that it can block mo...
Relevant standard
Ultraviolet protection factor (UPF)
Definition: UPF is a measure of the ability of a fabric or material to block ultraviolet light, and in the case of sunglasses, it reflects the ...
